ESL systems typically include a plurality of ESLs for each merchandise item in a store. ESLs display the price of corresponding merchandise items on store shelves and are typically attached to a rail along the leading edge of the shelves. A store may contain thousands of ESLs to display the prices of the merchandise items. The ESLs are coupled to a central server where information about the ESLs is typically maintained in an ESL data file which contains ESL identification information and ESL merchandise item information. The central server sends messages, including register update messages, to the ESLs.
An ESL includes a variety of components, such as, for example, a liquid crystal display (LCD), a transmitter, a receiver, ESL circuitry and memory, all of which may be powered by a battery. Replacing the battery in an ESL is a manual process which may involve a store employee going to the location of the ESL, removing the discharged battery and inserting a new battery into the ESL. Increasing the time between battery replacements would result in a lower cost of ownership for the ESL system owner by reducing both the number of replacement batteries which must be purchased and the amount of time store employees spend replacing the batteries. Given the large numbers of ESLs which are found in increasing numbers of retail establishments, the cost savings from the reduction of battery replacements can be significant.
To actively listen for commands or messages from the central server, the ESLs consumes battery power. However, in many situations, there are certain time periods when ESLs do not need to listen for messages because no messages are broadcast during those times. For example, some stores may not transmit messages to ESLs during the day, other stores may not transmit messages to ESLs during the night, or messages may be transmitted only at scheduled times.
Therefore, it would be desirable to provide an ESL system and method that conserves battery power by removing power from certain ESL components which are utilized to monitor for a received message during time periods in which the ESL is not receiving any messages.